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■ j|^ Agriculture 


Research Direction generale 
Branch de la recherche 

Contribution 1983-22E 

High tension 
high tensile fencing 


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representing Agriculture Canada 
research establishments 




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High tension 
high tensile fencing 

Range Research Station 
Kamloops, British Columbia 

Research Branch 
Agriculture Canada 

Copies of this publication are available from: 

Dr. D.A. Quinton 

Range Research Station 

Research Branch, Agriculture Canada 

3015 Ord Road 

Kamloops, British Columbia 

V2B 8A9 

Produced by Research Program Service 

©Minister of Supply and Services Canada 1983 


Many fence designs in use in Canada today are carry- 
overs from early traditions and technology. These 
fences are expensive, labor intensive and in most 
cases, overdes i gned . Research has resulted in new 
technology, new materials and in a better understand- 
ing of the capabilities and functions of nonelectric 
fence materials and fences. This bulletin outlines 
new advances in fencing technology and construction 
methodology. Implementation of construction technol- 
ogy alone can reduce fencing costs by 40%. Even 
greater savings can be achieved by using new materials 
This bulletin will aid anyone concerned with non- 
electric fencing, whether advising producers or 
erecting a fence. 


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LAWS 22 




































- 1 - 


Fences are a vital part of livestock and forage systems. 
Although they are primarily used to confine or exclude various 
kinds and sizes of livestock, they are also important in 
influencing animal movements and behaviour. Without good 
fences there would be no protection for crops, no control over 
breeding, feeding or safety of livestock and no established 
rangeland boundaries. 

Originally , 
around high 
Fencing the 
more benefi 
practical o 
barbed wire 
woven wire 
cheap wire , 
nology or i 
Posts were 
attached to 
were eventu 
set by poun 
little else 

fences co 
ly product 
n evolved 
t from les 
n an exten 

in the la 
a few year 

there was 
n understa 
spaced one 

them to s 
ally treat 
ding rathe 

was chang 

nsisted of stone or log walls placed 
ive fields and buildings for protection 
into a management tool used to obtain 
s productive lands. This first became 
sive scale with the introduction of 
te 19th century and the introduction of 
s later. After the introduction of 

minimal development in fencing tech- 
nding of the role of fence components. 

log apart and wires were tightly 
imulate the rigidity of logs. Posts 
ed to curtail rot, were sharpened and 
r than by backfilling and tamping, but 
ed until recent years. 

Today's high costs for land, machinery, fertilizer, fuel, feed 
and farm materials, as well as for labour, have dictated more 
efficient use of land. These economic conditions plus the 
need for replacement of many fences erected in the 1940's, 
with inexpensive labour and materials, have intensified the 
need for good low cost fences. This has, in turn, led to 
research to identify what constitutes good fences and fencing 
methods. This research has led to the use of high tension 
fences constructed of either barbed wire or high tensile 
smooth wire and to electrification of the latter. The best 
fence is the lowest cost fence that will do the required job 
over the greatest period of time. 



The basis of a modern fence is a pair of anchors, "brace 
assemblies", between which wires are strung. Posts are set 
in line between the brace assemblies to maintain wire spacing 
and to support the wires. The wires are loosely attached to 
the posts with staples. Wire spacing is further stabilized 

- 2 - 

by the attachment of droppers or stays. All of these compon- 
ents act together as a unit in which resilient materials, 
correct anchoring and a good right of way are exploited to 
produce an economical and effective fence. 


To understand fence function and performance, it is necessary 
to have a knowledge of the forces placed on a fence. Most 12^ 
gauge wire used today has a breaking strength of 450 kg for 
barbed wire and 590 kg for smooth (high tensile) wire. A 
brace assembly with five wires attached, each tightened to 
136 kg tension will thus have to hold a sustained force load 
of 680 kg. The brace assembly, being the anchor for the 
fence, and the component giving strength to the fence, must 
withstand the tensioned force of the wires plus any additional 
forces up to the point at which the wires break. 


Posts and their setting are the most exp 
construction. Therefore, the fewer post 
expensive a fence will be. The primary 
posts are to maintain proper wire spacin 
weight of the wire, prevent overturning 
the fence; they are not required to add 
or rigidity to the fence. Thus line pos 
intervals from 10 to 30 m apart. The ac 
dependent upon the terrain and the purpo 
Research has shown that fencing costs ar 
reduced with post spacings greater than 

ensive items in fence 
s required, the less 
functions of line 
g, absorb some of the 
and add visibility to 
appreciable strength 
ts can be spaced at 
tual post spacing is 
se of the fence . 
e not appreciably 
18 m. (Fig. 1) . 


w 240Q 


<u 2100. 

<u i8oa 


6m 1 2m 1 8m 
Fiaure 1. Post spacing versus fence costs 

- 3 - 


Wire is a restraining tool that plugs the holes between posts 
and brace assemblies. Fence wire should be sufficiently 
elastic to withstand applied stress forces and should be 
galvanized to retard rust. Barbed wire must be prestressed to 
270 kg to straighten the twists before it will behave elasti- 
cally to applied forces. High tensile wire, being a single 
strand, does not need pres tress ing . Wire should be attached 
firmly to brace assemblies at a standard tension of 136 kg at 
C or equivalent. 

The barbs on wire are essentially a hold over from the days of 
low tensile strength wire when it was believed that they were 
an important deterrent to animals. Research has shown that 
the elastic, unified performance of modern fence designs is a 
more effective deterrent. A panel of wire fence, cross braced 
with droppers, moves with the animal challenging it, yet does 
not allow the wires to be spread and the fence breached. 




fasteners are the me 

to brace 

assemblies and the mea 

mai n tained 

on line posts. Bein 

an a t tac 


g tool, staples shou 



wire on line posts. 

staple crown and the wire on li 

s lide be 

tween the staple and th 

express ion 

of elastic action of 

loads o ve r 

the entire length of 



htly against the wir 

short, in 


endent, more rigid 1 



break under stress 1 

ans by which wire is attached 
ns by which wire spacing is 
g a spacing tool rather than 
Id not be driven tightly 

Leaving a space between the 
ne posts allows the wire to 
e post. This allows for 
the wire and distributes stress 
the wire. Conversely, driving 
e on line posts results in 
engths of fence that will 
oads . 


Droppers, or stays, are used to maintain wire spacing between 
posts and to give visibility to the fence. They also function 
in distributing stress forces over all of the fence wires. 
Droppers should be inexpensive, easily attached and strong 
enough to resist bending or breaking under stress loads. 




Common practice and belief is that fence posts must be close 

- 4 - 

together with wire tightly attached to them to make a strong 
fence. The facts are, however, that with tensioned wire, the 
reverse is true. When an impact force is applied to a fence 
wire, the lateral forces acting on the posts will lessen with 
increasing distance between them (Fig. 2) . 

Figure 2. Effect of Post Spacing on Lateral Loads 

Appl ied to a Fence. 

This means that closely spaced posts must absorb more of the 
force of an impact on the wires and the chance of post failure, 
by breaking or overturning, is increased. If the staples 
holding the wires have been driven tightly against the wire, 
the problem is compounded. These short spans behave as indiv- 
idual fences and are required to absorb the total stress load 
applied to them, greatly increasing the chance of failure of 
both posts and wires. 


ELASTICITY. Pre tension 
high tensile steel wire 
an applied tension, up t 
of the wire. The stress 
mately linear to the yie 
percent of the breaking 
is subjected to a tensio 
wire will return to its 
is removed. However, if 
point the wire will be p 

ed (straightened) barbed wire and 
elongate at a rate proportional to 
o the elastic limit or yield point 
-strain relationship is approxi- 
ld point which is about eighty 
strength of the wire. If a wire 
n less than the yield point the 
original length when the tension 

the tension exceeds the yield 
ermanently stretched. 

STAPLING. Driving staples tightly against the wire on 
line posts interferes with the wire's elasticity and 
reduces the wire's tolerance to impacts. Very little 

- 5 - 

force is required to deflect such rigid wires and small 
forces result in the generation of large wire tensions 
in short spans of fence. However, if the staples are 
not driven tightly against the wire the deflection due to 
impact is distributed over a greater length of wire and 
the elongation per meter of wire is very small. As a 
result, a minimal increase in wire tension is generated. 
To illustrate this principle consider: 

i. Post spacings of 6 m ; 
ii. Elongation rate of wire of 0.93 mm/m/100 kg ; 
iii. Original wire tension of 136 kg; 
iv. Brace assemblies (wire attached tightly) spaced 
2 00 m . apart . 

Condition 1. Staples are driven to hold wire tightly to 
line posts and a force sufficient to deflect a wire 30 cm 
is applied. 

Solving the triangle, the resultant elongation in the 
wire is then 2 ( /3m^+30cm^- 3m) - 30 mm over the 6m wire 
or 5 mm (30 mm t 6m) per each meter of wire. Since wire 
elongates at 0.93 mm/m for each 100 kg applied, an elong- 
ation of 5 mm/m results in an increase in tension of 
about 538 kg (5 mm/m f 0.93 mm/m/100 kg) . Since the wire 
was originally tightened to 136 kg tension, this increase 
will exceed the tensile strength of the wire. If the 
staples and posts hold, the wire will break. Otherwise, 
posts will be pulled loose, staples will be pulled out 
and the wire will be permanently stretched. 

Condition 2. Staples are driven to allow wire movement 
between post and crown of staple and a force sufficient 
to deflect a wire 30 cm is applied. 

Solving this triangle, the resultant elongation in the 
wire is then 2 ( /3m z +30cm z -3m) - 30 mm spread over 200 
meters of wire or 0.15 mm (30 mm i 200m) per each meter 
of wire. Since wire elongates at 0.93 mm/m for each 
100 kg of load applied, an elongation of 0.15 mm/m results 
in about a 16 kg (0.15 mm/m -: 0.93 mm/m/100 kg) increase 
in tension. 

This, added to the original tension (136 kg + 16 kg) , is 
well within the elastic limit of the wire. The wire 
would withhold the force (turn the animal) and return to 
its original length and tension when the force was removed 
There would be no damage to the fence. 

- 6 - 

Remember , when the staples are driven to hold the wire 
tightly to line posts, relatively small deflections 
(small loads) result in relatively large wire tensions 
and the yield point of wire is more likely to be 
exceeded. The wire and fence are then more suscep- 
tible to permanent damage, sagging and failure. 

TEMPERATURE. Another factor affecting wire which 

should be considered is expansion and contraction with 

changing temperatures. A 5 C change in temperature 

results in a 5 kg change in wire tension, independent 

of length. Thus allowances for temperature must be 

made when tightening fence wires or a means to readily 

change wire tension must be incorporated in the fence. 

Recommended wire tension is 136 kg at C; 126 kg at 

10°C; 116 kg at 2 ° C etc. 


Brace assemblies should be placed as far apart 
as the terrain will allow, up to a maximum separation 
of 400 m. Braces are the anchors for the fence wire so 
must be as square and as strong as possible. 

Brace posts tend to rotate on their axis in shifting to 
equilibrium when tension is applied and brace components 
come under compression. Only 25 mm of such movement can 
reduce tension by half in a 100 m span, thus tension in 
a 100 m fence tensioned at 45 kg is reduced to 23 kg. 
However, the same movement (25 mm) in a 200 m fence 
would only reduce the tension by one quarter from 45 kg 
to 34 kg. 

Test results of the force at failure of several types 
of brace assemblies (Fig. 3) are given in table 1. 
Since all double brace assemblies tested were strong 
enough to withstand forces sufficient to break the fence 
wires, type 3 was selected as the standard for end and 
corner braces. This brace is easy to build, will 
compensate for less exacting workmanship and is aesthetic' 
ally pleasing. In situations where a single brace is 
desired, a type 4 would give sufficient strength. Type 
4 braces must be built to exacting specifications. 

- 7 - 

pulMJA - M Uu lllOo, 

III I'fi // 


mm * urn 1 1 a (U *>>• *-/<•■/, 


Type 6 


Figure 3. Types of Brace Assemblies Tested 

- 8 - 

Table 1. Strength of brace assemblies at failure (215 cm 

mm post driven 76 cm) 









De flection 



De flection 

Load at 


at 680kg 

Fai lure 

at 680kg 



15 . 2 






1633 kg 


19 .6 




12 .2 


1451 kg 


29 .0 




12 .4 


1315 kg 


3 . 3 




3 . 3 


2540 kg 


8 .4 






1769 kg 


4 . 3 




2 . 3 


1451 kg 




The most suitable material for high tension and high tensile 
fence construction is wood, specifically sharpened round wooden 
posts that can be driven into the ground and that have been 
chemically treated to resist rot. Softwood posts, such as pine, 
absorb chemicals well, are light in weight, fairly strong and 
inexpensive, and have a long life expectancy. 

Pressure treated posts are relatively straight and are sharpened 

to facilitate driving. Posts vary in diameter from end to end 

and from post to post. All diameters specified in this bulletin 

are minimum recommendations and refer to the smallest end of the 
post . 

Posts, t re 
a vai lable . 
whi ch wi 1 1 
soaked, or 
a vo ided . 
They will 
need repla 
must be s t 
entire fen 
i ng . By t 
exceed 110 
of the wei 
forces act 
pine posts 

There are 
able manuf 

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Prope r 

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which h 

Such pos 

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rong eno 

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ght of t 

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ave h 

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By t 

ugh t 

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o wi 

re s 
n wi 
re a 
re . 



athe r , 
unde r 
ars . P 
rese r va 
i nexpe 
i ve ly s 
can e xe 
re fenc 
nd must 
Test r 
. 4 and 

rot , fire a 
pressure wi 
os t s whi ch 
t i ve br ushe 
ns i ve , but 
hor t time b 
posts used 

the wire t 
impact stre 
rt forces o 
e . Line po 

absorb par 
esults for 

Table 2. 

nd termi 
11 resul 
have bee 
d on the 
they are 
efore th 
i n brace 
ens ion o 
s se s wit 
n end po 
s t s must 
t of any 

tes , are 
t in posts 
n dipped , 
m should be 

poor value 
ey will 

as semblies 
f the 

hou t f ai 1 - 
s t s that 

carry part 



treated posts avi lable from reputa- 
r should satisfy himself of the 

9 - 

Figure k. Average Breaking Strengths for Pressure-treated 
pine posts with loads steadily applied. 

Table 2. 

Lateral loadbearing capacities of driven posts 



Depth Kg 
Driven (cm) Force 


102 mm 

10 2 mm 

10 2 mm 

12 7 mm 

12 7 mm 


Soft clay 
Medium clay 
Stiff clay 
Very stiff clay 
Soft clay 
Medium c lay 
Stiff clay 
Very stiff clay 
Soft clay 
Medium clay 
Stiff clay 
Very stiff clay 
Soft clay 
Med i urn clay 
Stiff clay 
Very stiff clay 
Soft clay 
Medi urn c 1 ay 
Stiff clay 
Very stiff clay 






o ve rturn 












o ve rturn 












ove rturn 









ove rturn 



ove rturn 









over tu rn 



ove rturn 







Greater than 130 mm lean, 

- 10 - 

quality of preservative, and methods of preserving used 
before purchasing posts. It is too late to return an inferior 
product after it has been in the ground for a year or two. 
Recommendations are given below. 

Preserving chemicals can cause reactions in people susceptible 
to allergies. The use of protective full-length clothing, 
gloves, and eye or face shields is necessary when working with 
chemically treated posts. 


Penta-Trea ted Posts. Pentachlorphenol is a wood 
preservative used to treat softwood posts. The dry 
chemical is mixed with oil and forced into the wood in 
a pressure chamber. Pentachlorophenol crystals 
remain in the wood when the pressure is removed. Penta- 
treated posts should contain a minimum of 4.0 kg of 
pentachlorphenol per cubic meter of wood, or meet CSA 
Standard 080.5. 

CCA Treated Posts. Chromated copper arsenate 
dissolved in water is an excellent preservative for 
wood posts. Evaporation of the water, after pressure 
treating, leaves the salt, which is poisonous to 
decay fungi and insects, deposited in the wood. These 
posts are dry, do not have an oil residue and can be 
painted. They are a light green colour after treatment 
CCA treated posts should contain a minimum of 6.4 kg of 
chromated copper arsenate per cubic meter of wood or 
meet CSA Standard 080.5. 

Pres sure-Creosoted Posts. Creosote is the oldest and 
most widely used wood preservative. Pressure creosoted 
posts give excellent protection against moisture, 
insects, and decay, and are resistant to grounding if 
the fence is electrified. They can be expected to last 
an average of 35 years and up to 70+ years under dry 
conditions. These posts are fire retardant in that 
they surface char and then self extinguish. Pressure- 
creosoted posts should contain a minimum of 96.0 kg of 
creosote per cubic meter of wood or meet CSA Standard 
080. 5 

- 11 - 


On even-contoured terrain, the post spacing of range fences can 
be 18 m or greater if droppers are installed between the line 
posts. The number of droppers depends on the type of livestock 
and the intensity of pressure on the fence. Under range 
conditions with light to moderate livestock pressure on fences, 
one dropper every 6 m is adequate. One dropper every 3 m is 
recommended for moderate to heavy livestock pressure and one 
dropper is required every 1.5 m for heavy livestock pressure. 

Droppers should not bend with normal impacts on fences. They 
should maintain wire spacings at all times and should have a 
life expectancy equal to that of the rest of the fence. 

llr/ *» «» KV«o *i«<" *"* tu *« 

Figure 5- Angle Grooved Wood and Snap on Metal 

Droppers . 

Many types of droppers are available in Canada. For most 
conditions either wooden or sheet metal droppers are recom- 
mended. Wooden droppers should be sufficiently rot resistant 
to last as long as the fence. Wood droppers are often made 
from cut saplings in forested areas, from treated 25 x 100 mm 

- 12 - 

lumber, or from 38 x 38 mm split cedar. Sheet metal droppers 
are fabricated from 18 gauge galvanized steel. Another 
popular dropper, which is inexpensive and easy to install, is 
made from twisted wire. However, these droppers permanently 
bend under very light loads or impacts. Because of this, 
twisted wire droppers should be used only on fences subjected 
to very light livestock pressure. 

Since droppers are not driven into the ground, they must be 
firmly attached to the fence wires. Droppers may be smooth, 
notched or grooved to accept fence wire and either snap or 
are wired or stapled onto the fence wires. 

If slotted wood or sheet metal droppers, which snap onto the 
wire, are used, care must be taken to insure that the droppers 
will not slide along the wire after installation (Fig. 5) . 
This is best prevented by insuring that there is a slight 
offset in wire grooves during manufacture. 


All wire for high tension and high tensile fences should be 
12*2 gauge triple galvanized (Type III) steel wire. To be 
safe and function properly, barbed wired should have a tensile 
strength of at least 4900 kilograms per square centimeter. 
High tensile wire should have a tensile strength of at least 
9800 kg/ Table 3 shows a comparison between character- 
istics of barbed and high tensile wire. 

Table 3 . Wire Specifications 


D i a Strength Elastic Limit 

Wire Type Gauge mm Kg Kg/cm 2 Kg Kg/cm z 

Barbed 12*5 2.54 431 4921 399 4007 

High tensile tying 12 2.69 590 10545 499 8928 

High tensile fence 12*5 2.46 644 12441 485 10179 

Max-ten 200 fence* 12 3 s 2.51 823 16576 735 14760 

* United States Steel tradename 

-13 - 


1. Cheaper than barbed wire (less than half price for 
equal length ) . 

2. Easier to string out and handle. All of the wires 
can be strung out and tightened in the same opera- 
tion since there are no barbs to tangle with other 
wires or vegetation. This feature alone can save 
walking 9 km for each 1.6 km of 5 wire fence 
constructed . 

3. Safer for livestock and wildlife, no barbs to 
damage hide . 

4. It behaves elastically along the entire length of 
wire since there are no barbs to hang up on staples. 
Thus it tolerates greater shock loads. 

5. It does not require pre s tret ching to obtain elastic 
properties . 

6. It has a greater tensile strength than barbed wire 
of the same gauge. 


STAPLES (Fig. 6) ; It is recommended that staples not 
be fully driven into line posts. Thus longer staples 
are needed. These should be 4.5 centimeters long, 
corrosion resistant with opposing slash cut points. 
Galvanized staples have a greater holding power than 
smooth staples. Staples should number about 60 per 
4 50 grams . 

DOWEL PINS, SPIKES. Dowel pins of varying length or 
spikes, will be needed for constructing brace assemblies 
Both should be corrosion resistant. Spiral spikes will 
hold better than smooth or coated spikes, but are 
difficult to remove. 

END POST FASTENERS. Wire may be tied off at end, corner, 
and gate posts by using various knots. Tests have shown 
that these reduce wire strength by 40% and are the weak- 
est part of the fence. They are presented here as an 
alternative to mechanical fasteners. 

- 14 - 


Barbed W ire . It is traditional to tightly staple 
barbed wire to brace and end posts, and to anchor the 
wire by double wrapping around the end post and fastening 
along the line wire by tightly twisting around the line 
wire. This works well if staples are driven snugly 
against the wire, but not so tightly that the wire is 
weakened or damaged. In high tension fence, the staples 
on end and brace posts should be driven adjacent to the 
barbs, where possible, to prevent wire slippage in the 
direction of wire pull when the wire puller is released 
after tightening. 

Hi gh Tensile Wire . This wire may also be tied off at end 
or brace posts with a special knot (Fig. 7) after 
stapling to brace and end posts. To tie this knot, allow 
about 76 cm of wire beyond the end post and wrap this 
around the post from the livestock pressure side. Pass- 
ing the free end under the line wire, loop it back over 
the top of the line wire allowing several inches of 
clearance from the post. Pass the free end between the 
loop wire and the post, and pull, snugging the loop 
tightly against the post. Secure the free end to the 
line wire with pigtail wraps starting over the line wire. 

Figure 6. Staple 

Figure 1. Knot for tying off 
H igh Tens i le Wi re 

COMPRESS ION SLEEVES . These may be used to tie wire off 
at end posts and braces (Fig. 8) . Tests show that these 

- 1-5 - 

fasteners will retain 100% of the strength of the wire 
when properly installed. To use compression sleeves, 
leave about 60 cm of wire beyond the post. Before 
stapling, thread two or three oval sleeves onto the wire 
Slide these back beyond the post. Wrap the wire around 
the post from the livestock pressure side and thread the 
free end through the compression sleeves. Position the 
sleeves a few inches from the post and double crimp each 
sleeve with a swager (see Fig. 14. Page 20) . 

Figure 8. Oval Compression Sleeves 

Wirevise.* Another method of securing high tensile wire 
to end posts is with a Wirevise (Fig. 9) . A 9.5 mm hole 
is drilled through the end posts, at the desired wire 
height, at a slight angle away from the livestock side 
of the fence. Thread the wire through the hole and the 
wirevise. Slide the wirevise forward and embed it into 
the hole. The wirevise will clinch the wire when reverse 
tension is applied and will be flush with the post. Cut 
surplus wire off flush with the fitting. This fastener 

- 16 - 

is effective to 100% of the strength of the wire 

Figure 9. Reliable Wirevise for High Tensile Wire. 

WIRE SPLICING. Wire may be spliced with knots, which are 
generally effective to 60% of the strength of the wire, 
or with mechanical fasteners. Mechanical fasteners are 
effective to 100% of the wire strength when installed 
properly . 


Barbed Wire . The most common method of splicing barbed 
wire is to form about an 8 cm loop by bending one end of 
the wire back along itself and securing by wrapping 
tightly around the line wire. The free end of the 
joining wire is threaded through the loop and bent back 
along itself to form a similar loop secured by wrapping 
tightly around the line wire. 

H igh Tensile W ire. The knot most often used to splice 
this wire forms a figure eight (Fig. 10) . To tie this 
knot, overlap about 20 centimeters of the ends of the 
wires to be spliced, and bend a loop in the end of each 
around the other wire so that the loops are in opposite 
directions. Bring the end of the wire in each loop under 
itself so that the ends are pointing in opposite 
directions. Pull the loops tightly together. After the 

- 17 - 

wire is tightened, remove excess wire 

Figure 10. Figure Eight Knot for Splicing High Tensile 

Wi re 

COMPRESSION SLEEVES . These can be used to splice wire 
as well as to tie off wire at end posts (see Fig. 8) . 
Thread the ends of both wires through the sleeves. 
Double crimp each sleeve with a swager to complete the 
splice. Compression sleeves are effective to 100% of 
the breaking strength of the wire. 

WIRELINK . * A wirelink is available which will butt- 
splice high tensile wire by simply inserting both wires 
as far as possible into the ends of the fixture (Fig. 11) 
Pulling in the opposite direction locks the wire, giving 
100% of the breaking strength of the wire. 

Figure 11. "Reliable" Wirelink for High Tensile Wire 


Other items available for high tensile fencing include adjust- 
able in-line wire strainers with removable handles and in-line 
tension indicator springs (Fig. 12) . Both of these are perma- 
nent in-line fixtures in each span of fence. Unless other 
means are used to tension the fence wires, these should be. 
One ratcheted wire strainer per wire will allow a manager to 
tighten or relax the wire in relation to temperature. Their 
use provides an easy and efficient way of retaining correct 
tension in line wires. They also facilitate quick repairs and 
retightening should the fence break. 

^Reliable Electric Company Trademark 

- 18 - 

Figure 12. In-line wire strainer, handle, and tension indicator spring 

At least one tension indicator spring permanently installed on 
one wire of each span of fence is required. The remaining 
wires of each span of fence are tensioned by finger tuning to 
the wire tensioned with the spring. With practice this method 
is remarkably accurate. 


All forms of construction require an assortment of tools 
designed to do specific jobs. Few things are more frustrating 
than not having a needed tool or having a poorly designed tool 
that does not work properly. Tools required in erecting high 
tension fences are as follows: 


Wire benders - hand fabricated of metal to work 
with high tensile wire. A small pair of vice grip 
pliers works well too. 

Post hole auger. 

- 19 - 



Wire sheaves - these are constructed of 13 mm 
plywood and consist of aluminum rollers, either 
adjustable or fixed, and a means of temporarily 
attaching to line posts. They function in spacing 
line wires parallel to the ground when placing 
tension on a fence. For high tensile fences, spikes 
can replace the rollers or the wire can be pre- 
stapled since there are no barbs to hang up. A 
number of these will be needed depending on the 
terrain . 

d. Hand swagers - crimping pliers for compression 
sleeves. These are available commercially or can 
be fabricated from a pair of 450 mm bolt cutters 
with an 8 mm capacity. Drill a 9.5 mm hole to 
crimp a 3.97 mm oval sleeve that accepts barbed 
wire. Drill a 6.35 mm hole to crimp a 2.38 mm 
oval sleeve that accepts high tensile smooth wire 

e. Wire pullers - these should have smooth jaws to 
protect the galvanized surface if working with 
high tensile wire. 

f. Fencing pliers. 

g. Two man post pounder. 

hi Tensionme ters - hi is made by installing a 
h2 compression spring inside a pipe. A graduated 
8 or 9.5 mm plunger is attached to pass through 
the spring so a pull on both ends compresses the 
spring. One spring that works well is part 
number D4804 for a Morris Rod Weeder drill. This 
spring compresses 15 mm for every 45.4 kg load 
applied up to 272 kg. Other springs will work 
equally as well if calibrated. 

h2 consists of a straight piece of 20 mm x 50 
mm board 107 cm long. Drive two nails on a 
straight line 102 cm apart at the ends of the 
board. At the middle of the board drive a third 
nail 13 mm below the line joining the end nails. 
Tension is measured by pulling the fence line 
wire to just touch the centre nail and multiply- 
ing the scale reading by 20. 

Wi re reel 

- 20 - 



Figure 13. Special Fencing Tools 

- 21 - 

COMMON TOOLS (Fig. 14). 

a. Notched marking 
stick . 

b. 25 cm crescent 
wrench . 

c. 12.7 mm electric 
drill . 

d. Claw hammer. 

e. Hand brace and 9.5 
mm x 2 00 mm bi t . 

f . Saw. 

g. Plumb bob 

h. 18 meter chain 
or tape . 





Whether your fence will follow property lines, terrain contours, 
or is designed to facilitate cattle movement on your range, you 

- 2 2 - 

must establish boundaries. It is often advantageous to have a 
surveyor determine property bounds before perimeter fences are 
built. Then if it is desirable to fence on contours to 
facilitate cattle movement, an agreement can be struck between 
good neighbours. Remember, however, that the fence may outlast 
the neighbour. 


Check local laws to be certain that the fence you are planning 

will legally meet your specifications and requirements. Your 

district agriculturist should be able to provide this informa- 
tion . 


Locate hazards or constraints such as bogs, embankments, flood- 
ing, deep drifting, highways, railways, mining, recreation 
areas, etc. It may be necessary to provide special fencing for 
these areas. It is always a requirement to check with 
electrical, telephone, water, gas and sewer authorities regard- 
ing possible buried lines and for fencing of easements that may 
exist . 


Check your topography. Fencing in hilly areas and on curves 
can present special problems which require special construction 
techniques and materials. Remember that all wires on any fence 
should be parallel to the ground, which may require some 
grading or special fence assemblies. 


Check your soil. Soils can greatly effect the materials and 
methods of fencing. Generally, however, whether your soil is 
soft, medium or hard clay, or is sandy, the best method of 
setting posts is by driving. Tests have shown that the force 
required to pull a driven post can be ten times greater than 
that of a post set by digging, backfilling and tamping. 
Driving posts in hard soils may require small pre-augered holes 
in which to drive the post, but it may be worth the extra 
effort. Similarly, some situations may require a deadman be 
anchored in the bottom of a hole to hold a post in place. 

Table 2 (page 9) shows the effect of post diameter and depth 
of placement on the treated wood posts. 

- 23 - 


Consider what you expect of the fence. For example, a fence 
that is well designed for cattle on the open range may be 
ineffective in containing calves or yearlings in a confined 
pasture situation. Usually, perimeter or boundary fences must 
be more secure and versatile than division fences. Perimeter 
fences must often contain more than one kind of livestock, 
protect crops, or turn away wildlife. Your plans, and a 
knowledge of animal behaviour, will be helpful in designing 
your fence . 


Fences should be designed so they are more than dividing 
barriers. Fences should also be an aid in livestock manage- 
ment allowing for efficient movement of livestock, easy access 
to water, increased forage utilization, ease of movement of 
livestock, and ease of movement of farm machinery. 


Sketch your layout and itemize materials. This should include 
fence dimensions, corners, angles at change of direction, gate 
locations and widths, rises and dips, etc. that can influence 
materials or construction. From this sketch it is possible to 
determine the number of posts, amount of wire, staples, fast- 
eners and other hardware that will be required. Further, the 
costs involved can be estimated more accurately before the job 
is started 


High tension fences are versatile and it is possible to select 
a design for practically any requirement or set of requirements 
These fences can be easily modified by adding or removing wires 
Smooth wire fences can also be electrified. Many fences are 
overdesigned for their intended purpose. While these fences 
may produce additional safety, the extra materials and labour 
involved may nullify any benefit gained. Following are 
specifications for several fence designs. 


These designs are adequate for cattle on range where there is 
not unusual crowding to force calves against the fence. They 
allow wildlife to move freely by crawling under, or jumping the 

- 24 - 

fence. The 101 cm fence is used in areas of high deer traffic 
Cattle, particularly bulls, will have a tendency to attempt to 
jump low fences. 

Height of top wire 101 cm or 116 cm. 

Wire spacing from ground up: 

(116 cm fence ) 

Wire spacing from ground up: 
(101 cm fence ) 

38 cm, 25 cm, 25 cm, 28 cm. 

38 cm, 20 cm, 20 cm, 23 cm 

End post length & diameter: 244 cm x 152 mm, driven 122 

cm . 

Brace post length & diameter:244 cm x 101 mm, driven 122 

cm . 

Top brace : 
Line posts : 
Post spacings; 
Droppers : 

Wire tension : 

244 cm x 101 mm 

200 cm x 76 mm driven 76 cm 

18.5 m 

metal snap on or wood 38 mm 
x 28 mm, 3 m spacing. 

Tension barbed wire to 270 
kg to remove kinks, then 
relax and fasten at 136 kg 
at 0°C or equivalent, to 
gain elasticity. 


The five wire high tensile wire fence is a range fence replac- 
ing the four wire barbed wire fence. The five wire barbed wire 
fence is a fence for medium to heavy livestock pressure. 

Height of top wire 

114 cm 

Wire spacing from ground up: barbed wire - 31 cm, 20 cm, 

20 cm, 20 cm, 23 cm. 

End post length & diameter 

Brace post length & dia: 

Top brace : 
Post spacings : 

high tensile- 40 cm, 18 cm, 
18 cm, 18 cm, 20 cm. 

244 cm x 152 mm, driven 
12 2 cm . 

244 cm x 101 mm, driven 122 
cm . 

244 cm x 76 mm, driven 76 cm 

up to 18.5 m 

- 25 - 

Droppers - 

galvanized metal snap 
on or wood : 

38 mm x 38 mm, spaced at 4.6 m for 
light grazing pressure, 3 m for 
moderate to heavy grazing pressure 

Wi re tension 

Tension barbed wire to 270 kg to 
remove kinks, then relax and 
fasten at 137 kg at 0°C or equiva- 
lent to gain elasticity. Tension 
high tensile wire to 136 kg at 
0°C or equivalent. 


This fence replaces the four or five wire barbed wire fence. It 
is designed primarily for moderate to heavy grazing pressure by 
large animals . 

Height of top wire: 

Wire spacing from 
ground up: 

116 cm 

33 cm, 15 cm, 15 cm, 15 cm, 18 cm 
20 cm . 

End post length & dia: 244 cm x 152 mm, driven 122 cm. 
Brace post length & dia:244 cm x 101 mm, driven 122 cm. 

Top brace : 

Line posts (minimum) 
Post spacings : 
Droppers : 

Wire tension : 

244 cm x 101 mm 

200 cm x 76 mm, driven 76 cm. 

up to 18.5 m 

galvanized metal snap on or wood 
4.6 m spacing for light grazing 
pressure, 3 m spacing for moder- 
ate to heavy grazing pressure. 

136 kg at C or equivalent. 


This fence will contain both small and large animals on range 
and will discourage some wildlife and dogs. 

Height of top wire: 

Wire spacing from 
ground up : 

117 cm 

10 cm, 13 cm, 13 cm, 13 cm, 15 cm, 
1 5 cm , 18 cm , 20 cm . 

- 26 - 

End post length & 

diameter: 244 cm x 152 mm, driven 122 cm 

Brace post length & dia:244 cm x 101 mm, driven 122 cm 

Top brace 
Line posts : 
Post spacings : 
Droppers : 

Tension : 

244 cm x 101 mm 

200 cm x 76 mm, driven 76 cm 

up to 18.5 m 

galvanized steel snap on or wood 
4.6 m spacing for light grazing, 
3 m spacing for moderate grazing, 
1.5 m spacing for heavy grazing 
pressure . 

136 kg per wire at C or equiv- 
alent . 


This fence will contain most kinds of livestock, turns away 
many small domestic or wild animals and may be used to replace 
woven wire. It is a deterrent to carnivores, especially if the 
second, fourth and top wires are electrified. 

Height of top wire: 

Wire spacing from 
ground up: 

End post length & 
diameter : 

Brace post length & 
diameter : 

Top brace : 

Line posts : 

Post spacings : 

Droppers : 

Minimum wire tension 

118 cm 

10 cm, 10 cm, 10 cm, 10 cm, 13 cm, 
13 cm, 13 cm, 13cm, 13 cm, 13 cm. 

244 cm x 152 mm, driven 122 cm. 

244 cm x 101 mm, driven 122 cm. 

244 cm x 101 mm 

200 cm x 76 mm, driven 76 cm. 

up to 18.5 m 

galvanized steel snap on or wood, 
4.5 m spacing for light pressure, 
3 m spacing for moderate live- 
stock pressure, 1.5 m spacing for 
heavy livestock pressure. (Do 
not use metal droppers on electri- 
fied fence). 

136 kg per wire at C or equiva- 
lent . 

- 2 


This design differs from other high tensile designs because of 
the increased livestock pressure. In this design, posts are 
either drilled for wire passage or are staggered on alternate 
sides of .the wire if livestock pressure will be on both sides 
of the fence . 

Height of top of wire: 133 cm. 

Wire spacing from ground 

up: 25 cm, 10 cm, 10 cm, 10 cm, 

13 cm, 13 cm, 13 cm, 13 cm 

1 3 cm . 

Gate post length & 

diameter: 244 cm x 152 mm driven 107 cm. 

End post length & diameter: 244 cm x 152 cm driven 107 cm. 

Brace post: 244 cm x 127 mm, driven 107 cm 

Top braces: 244 cm x 101 mm 

Line posts: 244 cm x 101 mm, driven 107 cm 

Post spacings: 3 m centers 

Wire tension: 136 kg at C or equivalent. 

Staples: 45 mm galvanized, slash 

points (not needed if posts 
are drilled ) . 

Tension devices: One in-line wire strainer per 

wire . 

Wire splices: Three crimped sleeves or 

Wi re links . 

Tension: 136 kg per wire at C or 

equivalent . 


This fence will secure full grown horses and foals, while 

di scour ageing small animals. The top and bottom wires can be 

electrified to discourage pawing and reaching over the fence. 

On high fences it may be necessary to drive posts which are too 
long to be driven by a hydraulic ram. In these instances, the 
post may be hand planted by augering and backfilling to a depth 
that will allow driving with the ram. The post can then be 
driven to the specified depth. 

- 28 - 

Height of top wire: 

Wire spacing from 
ground up : 

Gate post length & 
diameter : 

End post length & 
diameter : 

Brace post length & 
diameter : 

Top braces : 

Line posts : 

Post spacings: 

Wire tension : 

Staples : 

Wire splices : 

146 cm 

10 cm, 10 cm, 10 cm, 10 cm, 13 cm, 
13 cm, 13 cm, 13 cm, 13 cm, 13 cm, 
1 3 cm , 15 cm . 

274 cm x 152 mm driven 122 cm. 

174 cm x 152 mm driven 122 cm. 

274 cm x 127 mm driven 122 cm. 

274 cm x 101 mm. 

244 cm x 101 mm driven 91 cm. 

4.3 m centers 

136 kg at C or equivalent 

45 mm galvanized, slash points 

Three crimped sleeves, Wirelinks. 




Locate survey pins or stakes at ends of line and stand sighting 
poles a few cm beyond where the beginning and end of the fence 
will be. Place one or more intermediate poles and align all 
poles by sighting over the starting pole to the end pole (Fig. 
15) . 


— _ 




Figure 15. Sighting a Fenceline on Level Terrain 

29 - 


While rises or dips are in the sighting line, special tech- 
niques are involved. For a rise, set two sighting poles 
about three meters apart at the top of the rise, so that both 
can be seen from either end of the fence (Fig. 16) . When 
crossing a dip, place two poles and align these by sighting 
from the highest point on both sides of the dip (Fig. 17) . 



„ - " 

r / 




Figure 16. Sighting a Fencel ine over Rises 

Figure 17- Sighting a Fencel ine through Dips 


It is possible to run high tension wires around curves and 
corners without constructing brace assemblies. There are, 
however, certain details and extra care that must be taken. 
The exact location of posts must be measured and larger sized 
posts will often be needed. Posts need to be driven deeper 

- 30 - 

at a 10 cm lean off vertical toward the outside of the curve 
to allow for movement when tension is placed on the wires. On 
sharp curves, post spacings will be reduced and all wires will 
have to be stapled on the outside of all posts in curves. 

NOTE: See page 34 under "Construction" for 
directions on rounding corners. 



Remove all obstacles that will interfere with fence construc- 
tion, including small brush and tall grass. If possible, 
level the fence line. These practices will greatly reduce 
problems with construction and result in a straighter, easier 
to maintain, fence. 


Each section of high tension fence begins and ends at an end 
post, brace post or gate post. Thus the location and place- 
ment of these posts are the most important factor in how your 
fence turns out. They provide the anchors for the fence and 
are the first members of brace assemblies which must withstand 
the tension of the wire. The procedure for setting these 
posts is as follows: 

1. Select a straight 244 cm long post of proper 
diameter. Mark the exact location where it 
is to be placed and auger a pilot hole 
smaller in diameter than the post to a 90 cm 
depth. (This should be augered so the top 
of the post will lean 50 mm off vertical 
opposite the direction of pull of the line 
wires (Fig. 18) . Posts can be driven in 
some soils without preaugering pilot holes. 

2. Drive the post to a depth of 122 cm. Some 
soils may be particularly loose (bogs, etc.) 
in which case posts can often be strengthened 
by placing deadman anchors. 

- 31 - 

Figure 18. Proper 
placement of end 

— dj-4 — 50mm lean 
P~! Pull 


3. Proceed as above until all end posts are driven. 

which le 
is const 
10 cm tr 
and fast 
the anch 

eadman anchor - Fig. 19 shows a deadman anchor 
ssens excessive twisting of an end post. It 
ructed from a short piece (30 cm) of 10 cm x 
eated post. Cut one end of this on a 45° angle 
en a cable (made from twisting wire together) 

to it, about 10 cm back from the diagonal end. 
one side of the bottom of the augered hole, jam 
or in and pull it taut, forcing the anchor to a 

parallel to the soil surface. Drive the post 

Figure 19- Deadman anchor to prevent excessive twisting of end post 

- 32 - 

past the anchor and attach the cable to the post 
in the same direction as any twist that will be 
placed on the post by the line wires. 

It may be necessary to drive posts that are too 
long to fit under the ram of a post pounder. 
In these situations, a hole is augered and the 
post is set by backfilling and tamping to depth 
such that the post can be driven to the full 
specified depth by the post pounder. 


Proper stringing of the guide wire is the key to a straight 
fence and a fence which has all wires parallel to the soil 
surface . 

Level Terrain 


3 . 

Anchoring: Either anchor the wire reel (Fig. 14) or 
tie off the free end of the wire on the end post at 
the desired height for the bottom wire. If wire is 
tied off, a portable reel for paying out wire must be 
used . 

Pay out the wire, using the wire reel to avoid kinking 

the wire, in a straight line to the far end post. 

Maintain enough tension to prevent loops or 
s lack wire . 

recoi Is of 

Proceed about 90 cm past 
puller to the free end of 
until taut (about 45 kg t 
desirable that wire pulle 
prevent damaging galvaniz 

Make sure the wire is str 
Whip the wire up and down 
accomplish this. 

Wrap the wire from the li 
secure the wire back onto 
height of the bottom wire 
either an end post tie of 
with a Wirevise. (See pa 

the end post, attach a wire 

the wire and pull it up 
ension). NOTE: it is 
rs have smooth jaws to 
ation of the wire. 

aight between the posts, 
or add more tension to 

vestock pressure side and 
itself at the premarked 
Temporarily tie off with 
f knot, a crimped sleeve or 
ge 13 on end post fastening) 

Uneven Terrain 

1. Locate the guide wire by either using the sighting 
poles or by driving permanent posts at the top of 
rises. If permanent posts are used, care must be 

- 33 - 

taken in post location (use sighting poles) and in 
the size of post used in relation to its ultimate 
function as part of the finished fence. 

Pay out the wire on the livestock pressure side of 
the fenceline. Attach a wire puller to the wire 
and tighten the wire to 45 kg. If permanent posts 
have been driven, wire sheaves (Fig. 13, page 20) 
can be used to guide the wire. If the sighting 
poles are used, care must be taken in relation to 
the terrain. In the case of high points, the wire 
will be resting on the ground, but it will be 
bridging the dips. 

If wire is on the ground, raise and whip it up and 
down at the highest point on each rise to get it 
straight and touching the sighting poles. Mark 
locations for driving rise posts. NOTE: When 
driving posts, insure that they are 13 mm off the 
guide wire. This maintains a straight fence. 

Drive rise posts, attach wire sheaves or staple 
smooth wire at desired height for bottom wire. 
(See section on stapling, page 47) . 

Near the sighting poles in each dip, mark the loca- 
tions for dip posts. This may be done by using a 
plumb bob (Fig. 20) if you can reach the guide wire, 
or by sighting using the sighting poles (Fig. 17) . 

Figure 20. Use of plumb bob for locating 
post position in dips 

Drive a 244 cm post to a depth of 122 cm at the loca- 
tion of each dip post. 

Reduce the tension on the guide wire sufficient to 
pull it down to the bottom wire height on the dip posts 
Wire sheaves or stapling smooth wire can be used to 
guide the wire. Retighten the wire to 45 kg. NOTE: 
An alternate method of handling large dips is to allow 

- 34 - 

bridge the dip permanently (Fig 
does not necessitate lowering 
liscussed above, 
A short 
:he fence 
136 kg 

Figure 21. Bridging a Narrow Gully with High Tension Fence 


Line posts in curves should be set before stringing the guide 
wire using the following techniques: 

Shallow - one post curves 

1. For change of direction less than 20 degrees (Fig. 22) . 

Figure 22. Rounding a Shallow One Post Curve 

2. Set stakes on the fence line at the beginning and end of 
the curve . 

- 3 

3. Stretch string between these two stakes, A and B. 

4. Mark the mid point (C') and measure the perpendicular 
distance to what would be the fence line (C) had it 
continued in a straight line from stake A. 

5a. If the distance in '4' above is less than 61 cm, drive 
a 244 cm x 100 mm post 122 cm deep at the point (C) of 
intersection with the original fence line. 

b. If the distance in '4' is from 61 cm to 122 cm, drive 
a 244 cm x 127 mm post at the point of intersection. 

c. If the distance in '4' is greater than 122 cm but not 
more than 178 cm, drive a 244 cm x 152 mm post at the 
point of intersection. 

Note: The post should be driven at a slant of 10 cm 
off perpendicular toward the outside of the curve. 
On fences with less than seven wires, the diameter of 
posts can be reduced by 25 mm. 

Rounding a long gradual curve 

This is a continuation of the one post shallow curve technique 
The position of each post is determined from the previously 
set curve post driven 10 cm off the perpendicular to allow for 
movement when the wires are tensioned. Posts will be at A, C, 
B , D , etc . 

Figure 23. Rounding a Long Gradual Corner or Curve 

ounding a sharp corner or curve (Fig. 24) . 

imilar to rounding a shallow corner 

1 ean 

Rounding a sharp corner or curve (Fig. 

Rounding a sharp corner is similar to r 
or curve, but all posts are 244 cm x 15 
toward the outside. The post spacing i 

toward the outside. The post spacing is re 
curve radius. However, posts should not be 
cm apart to maintain soil stability. 

_> 2 mm with a 101 mm 
is reduced to fit the 

"t less than 122 

- 36 - 

Figure 2k. Rounding a Sharp Corner or Curve 

NOTE: Use caution when tensioning wire around curves to ensure 
wire (especially barbed wire) does not hang up on the post. 

- 37 - 


Braces should be constructed at corners, ends of fences, at 
gates, and in the fence line at appreciable changes in slope 
of the terrain . 

Braces generally should not be spaced more than 400 m 
apart . 

All posts in brace assemb 
x 123 ram and should be dr 

All diagonal wires used o 
12^ gauge and double or t 
breakage . 

All joints should be care 
dowel pins or spikes as f 
be corrosion resistant an 
89 ram longer than the pos 

Line wires are tightened 
end post of the brace so 
then fastened snugly to t 

type 3 (page 7 ) braces. The 
exacting) , and are sufficient 
fewer wires, described in thi 
assemblies should be used wit 
for corner assemblies. Doubl 
cases where smaller posts are 
a full 122 cm, or in loose or 

lies should be at least 244 cm 
iven at least 122 cm deep. 

n braces should be at least 
riple wrapped to prevent 

fully constructed using either 
asteners. Dowel pins should 
d spikes should be at least 
t di ame te r . 

and fastened securely to the 
the pull is through the brace, 
he first and second braceposts. 

re are construction techniques for 

se are easiest to build (less 

ly strong for all fences, of 12 or 

s bulletin. Double brace 

h fences of 7 or more wires and 

e braces should also be used in 

used, when posts are not driven 

boggy soils . 

Figures 25 through 33 show various brace assemblies. Note: 
Inside brace assemblies, as shown in figures 30, 31 and 32, 
are subject to cattle rubbing on them in areas of moderate to 
high cattle pressure. This should be considered in construc- 
tion of these braces. 

Figures 25 to 32 on following pages. . 

- 3 8 - 

mm f 
1 ean 

25mm lean no 1 ear, 



End post Brace posts 

Figure 25. Corner Brace Assembly Showing Joint Detail using Pins 

Di rect ion of pul 1 


"W // 

End post 

^^\ // 

25 mm lean 



• Brace post 

no lean 


Ul t i *■ 


<« «<«/*•«** «"/ t*4iti, ii*/**4, 

/ '*t **<4df+t/ f4*St *fd *-C d-/^ 



1 1 

1 1 

Posts driven 122 

cm i • 

Figure 26. Single Span Brace Assembly 

- 3' 

Di rect ion of pu 1 1 

Brace post 
no lean 


Brace post 
25mm lean 

Posts driven 122 cm 


Figure 27. Double Span Brace Assembly 



Figure 28. Double Rrace Assembly for Rise Posts 

- 40 - 

Figure 29- Double Span Dip Assembly 

Sight 1 i ne 

i ne wi re 

Assembly bisects 
ang le 

Figure 30. Medium Corner Brace Assembly for Change 
of Direction Greater than 20° but Less than 60° 

- 41 - 

200cm x 100mm post 

25mm lean toward line wires 

f^f «•#••• **• 

2^cm x 127mm post 
50mm lean into 
1 i ne wi res 

Figure 31. Medium Corner Brace Assembly (Fig. 30) Showing Construction 

Figure 32. Double Brace Assembly for Shallow Corner in Soft 

or Boggy Soi 1 s 

- 42 - 


^ u ■ o 



















_. _ _ 

Figure 33- Double Brace Assembly for Angles Greater than 60 

Construction Procedur e 

Having driven the end posts, rise posts, corner posts and gate 
posts and strung and tensioned the guide wire, lay a 244 cm x 
101 m top brace on the ground parallel to the guide wire and 
butt it against the end post to measure the location for 
driving the first brace post. Holding the guide wire aside, 
drive the post 122 cm deep with a 2.5 cm lean opposite the 
direction of pull of the line wires. 

Note 1: All post holes may require pre-augering a 7 cm hole 
90 cm deep . 

Note 2: Allow 25 mm overlap for squaring of brace posts if 
spikes are used. 

Again, holding the guide wire aside, measure with the second 
horizontal brace and drive the second brace post without any 
lean. When the guide wire is released it should just touch 
the pos t s . 

If spiking, square the tops by removing not more than 13 mm of 
wood from the inside top of the brace and end posts and spike 
through the post into the ends of the horizontal brace. 

- 43 - 

If using pins: 

a) . Measure up 118 cm from the ground on the brace side of the 
end post and drill a 9.5 mm hole 51 mm deep parallel to 
the line wires . 

b) . Drive a 9.5 x 100 mm galvanized steel dowel pin 50 mm deep 
into the drilled hole in the end post. 

c) . Measure up the first brace post 118 cm and drill a 9.5 mm 
hole through the post parallel to the line wires. 

d) . Drive a 9.5 x 230 mm steel dowel pin through the post 

stopping when the pin emerges flush with the post surface. 

e) . Mark, drill and drive the pin in the second brace post 
similar to the first. 

f) . Drill a 9.5 mm diameter hole 51 mm deep in the centres of 
both ends of the horizontal top braces. 

g) . Lift the first horizontal brace and position it on the pin 
protruding from the end post, align it with the pin on the 
first brace post and drive the pin 51 mm into the first 
top brace leaving 51 mm of the pin protruding to receive 
the second top brace . 

Cut a 12.1 meter length of at least 12^ gauge fencing wire and 
bend a 15 cm loop in one end. Staple this or hook it over the 
protruding pin on the brace post. Maintaining hand tension on 
the wire, stretch a diagonal and wrap the wire around the end 
post under a horizontal staple and back over the pin or staple 
on the brace post. Complete two complete tight wraps in the 
same manner . 

Pull as much slack up as possible and staple the wire to the 
brace post. 

Facing the diagonal wires, opposite the livestock pressure side 
of the fence, insert a 38 mm x 50 mm x 60 cm treated twitch 
stick about 50 cm between the four diagonal wires, perpendic- 
ular to the wires so the end of the stick rests against the 
horizontal brace. 

Maintaining this length, tilt the stick toward the post so that 
the stick clears the top brace, and pull the stick toward you 
to twist the wires together. Make six or eight complete 
revolutions twisting the wires and stopping with the stick in 
the upright position. Tilt the stick back so it rests against 
the top brace and cannot unwind. 

Cut a length of wire and staple it over the end of the twitch 

- 44 - 

stick onto the top brace to secure the twitch stick. 

Bend the horizontal guide staples over the wire at the bottom 
of the end post and brace post to hold the wire. 

Install the second top brace similarly to the first one. 

Install diagonal wires similarly to the first one. 


1. Having set the end posts, and strung the guide wire, 

measure the location of posts by pacing or by stretching 
a tape and making a mark at the location of each post. 
Posts may be set 18 meters apart on level terrain or as 
far apart as the terrain will allow (up to 18 m) to 
maintain the wires parallel to the ground on uneven 
terrain . 

Lay out a 
dr i vi ng . 

198 cm x 100 mm line post at each location for 

Drive each post perpendicular to the soil surface to a 76 
cm depth to maintain a straight fence. Take care that 
posts do not push the guide wire out of alignment. It is 
a good practice to allow 13 mm to 20 mm clearance between 
the driven post and the guide wire. 

On uneven terrain, care must be taken to drive all posts 
perpendicular to the soil surface (Fig. 34) . This 
maintains maximum stability in the soil and maintains the 
fence he igh t . 

I rv.nrrect 


Gu i de wi re 

Figure 3k. Vertical Placement of Line Posts 

- 45 - 

Posts should generally be set on the downhill side of the 

wire on fences running across a slope and on the side of 

wire opposite the greater livestock pressure for more level 
situations . 


There are special considerations to make when working with wire. 
Barbed wire of course has barbs that catch and tear clothes and 
flesh and it will recoil when cut. High tensile wire is stiffer 
than barbed, is harder to bend and has a greater tendency to 
recoil than barbed wire. To cut wire, hold the needed end in 
one hand and step on the other end. If you must release a cut 
end secure it with something or push it several inches into the 
soil. Wear clothing that completely covers your arms and legs, 
heavy soled shoes, leather gloves and safety glasses. 

The nature of barbed wire practically dictates that wires be 

strung one at a time to avoid tangling. Since high tensile 

smooth wire does not tangle, it is possible to string all wires 
at the same time. 

To String Wire 

1. Load wire onto payout 
position, on the live 
tie off the wires beg 
bottom, or anchor the 

2. Slowly pay cut the wi 
as close as possible 
tension on the wires 
forming . 

3. High tensile smooth w 
on midpoint posts to 
loose enough for wire 
page 47 on stapling) . 

4. Continue to pay out w 
far end post. Mainta 
wires . 

5. Wires should be posit 
tension sheaves for b 
stapling for high ten 
that wires will be pa 
tightened, with no ne 
wires and thus change 

reels and beginning at end post 
stock pressure side of the posts, 
inning with the second from the 

wire ree 1 . 

res down the fence line staying 
to the posts. Maintain enough 
to prevent loops and kinks from 

ire may be periodically stapled 
guide the wire. Leave staples 
to slide through them. (See 

ire to about 152 cm beyond the 
in the payout tension on the 

ioned on posts with the use of 
arbed wire and periodic loose 
sile smooth wire. This insures 
rallel to the ground surface when 
ed to pull up or push down the 
the tension during final stapling 

- 4 6 - 

If an in-line wire strainer is not being used, cut the 
wire from the reel and attach a tensionme ter to it. 
If barbed wire is being used, tighten it to 272 kg, 
then relax to 136 kg and tie it off at the end post. 
Tighten high tensile wire to 136 kg and tie it off at 
the end post. If an in-line wire strainer is being 
used/ tie the wire off at an end post without tighten- 
ing it first. Staple all wires to the brace assembly. 

If in-line wire strainers (Fig. 12, page 18) are used, 
cut off each wire from the reel, position all wires on 
the end post and tie them off using an end post knot 
or crimped sleeves. Do not tension. 

a) . Return to the midpoint of the span; working from 
the top wire, attach a wire puller about 122 cm from 
the post and pull the wire tight. 

b) . Cut the wire at the midpoint of the slack between 
the jaws of the wire puller. Install an in-line 
strainer by threading two compression sleeves onto 
the wire nearest the post, and slide them back about 
30 cm. Thread about 15 cm of the wire through the 
holes in the shank of the in-line strainer and bend 
the wire back on itself. Slide the sleeves forward 
to catch the wire and crimp the sleeves. 

c) . Thread the line wire through the drum of the in- 
line strainer and cut off surplus wire close to the 
drum. Turn the drum to secure the wire and insert 
the ratchet pin. Continue turning to take up all 
slack. Remove the wire puller. 

d) . Continue as above for all wires using in-line 
strainers . 

e) . If an in-line tension indicator spring is to be 
used, attach it between the in-line strainer and the 
line wire in the second wire from the top. 


Fences constructed with a tensionmeter are tensioned at end 
posts before tying off. If proper construction techniques 
were followed, wires were spaced, and fences were tensioned to 
136 kg at 0°C or equivalent allowing for temperatures. These 
fences will remain well tensioned after the fence shifts to 
equilibrium, and no further tension adjustments need to be made 

The method for tightening fences utilizing in-line strainers is 
as f ol lows : 

47 - 

Starting with the wire witn' the in-line tension spring, 
attach a handle or wrench and turn the drum of the strainer 
until the wire is taut and free from other wires. 

If in-line tension springs are used, measure the coiled 

portio.n of the spring. Continue turning the drum until the 

coil is shortened 38 mm to 45 mm, which will give at least 
113 kg tension on the wire. 

Crank the remaining in-line strainers to about the same 
tension that was placed on the wire with the in-line tension 
spring. Check each wire against the spring tensioned wire 
by pulling toward you until the feel of the resistance is 
the same. With practice, this method is surprisingly 
accurate . 

To tension wires without in-line springs, draw the fence 
taut by cranking up the in-line strainers. Continue crank- 
ing the strainer and check the tension by measuring wire 
deflection using the apparatus and spring scale shown in 
Fig. 13, page 20. After tensioning the first wire, 
additional wires can be tightened by feel , making final 
adjustments by measuring deflection pressures with the 
board and scale. 

After all wires are tightened, staple all wires at their 
correct height on all posts following proper stapling 
techniques. Remove all wire sheaves before stapling. 


Wire should be stapled to line posts after it has been 
tensioned . 

Contrary to popular opinion, staples on line posts should never 
be driven tightly against the wire. Driving staples tightly 
increases friction on the wire and prevents even tension in long 
spans of wire. It also kinks the wire and results in short 
rigid spans with little or no elasticity to reduce the stress of 
livestock pressure against the fence. Tight staples also 
prevent movement of wires in response to temperature changes 
and, with imposed loads, stretching of the wires occurs, result- 
ing in sagging or breakage. 

Staples should be driven just tight enough so the wire could be 
removed and rethreaded through the arch of the protruding 
staple (Fig . 35) . 

- 48 - 

Figure 35. Proper Stapling 

A major failure of wire fences is caused by staples pull- 
ing out. This could be the result of several factors, 
including : 

1. Using the improper staple for the job; 

2. Stapling wires on the wrong side of the posts for 
livestock pressure; 

3. Wire stapled on inside of posts on curves; 

4. Excessive tension in the wires; 

5. Improperly driving the staples so there is little 
resistance to pulling. 

Proper Technique : 

1. Select the correct staples. The longer the staple 
the greater the hold. Tests show that 45 mm x 9 gauge 
staples driven in wood posts have 50% more resistance 
to being pulled out than 38 mm x 9 gauge staples driven 
into the same posts. For long life, all staples should 
be manufactured from galvanized wire, or hot-dip tumbler 
galvanized after forming. Staples should have slash cut 
points so the legs will bend with driving, giving the 
staple maximum holding power. 

2. Staples should never be driven vertically into wood 
posts. Doing so can cause splitting along the grain of 
the wood, resulting in little holding power of the staple 
Rotating the staple slightly off vertical straddles the 
grain, increasing the holding power of the staple. 

3. Staples with slash points should be driven so their 
legs curve outwards as they penetrate the wood (Fig. 36) . 
The slash cut acts as an asymetrical wedge forcing the 
leg to curve away from the flat surface. Tests show 
that staples driven so that each leg curves away from the 

- 4 9 - 

vertical centre line have 40% more pull out resistance 
than staples driven incorrectly 

I ncorrect 


Figure 36 

When placing a staple over the wire against the post, 
rotate the staple slightly (20° off vertical) away from 
the flat surface of the point on the upper leg (Fig. 37) 

Figure 37 

4. In dips, drive staples at an upward angle and on 
rises drive staples at a downward angle (Fig. 38) . The 
wire is then pulling the staple in on the post instead 
o f out . 

Figure 38. 
Stapl ing rise 
or dip wi res 

- 50 - 

5. On very steep dips or rises, where there is consid- 
erable wire tension pulling on staples, double stapling 
is advantageous (Fig. 39) . 

Figure 39- Double Stapling Rise or Dip Wires 

6. When stringing and tensioning line wires around the 
outside of posts stapling can be used to reduce friction. 
Simply hang a staple over the securing staple and 
between the wire and the post so the line wire is sliding 
on the staple rather than the post (Fig. 40) . 

Figure ^0. Stapling around Curves or Corners 


Dropper installation is the last operation performed in the 
erection of a line fence. Droppers are attached to the fence 
line wires after all wires are properly tightened and after 
final stapling has occurred. 

Droppers, acting as wire spacers and load distributors, must 
be properly installed to function properly. To space wires 
correctly, they must remain vertical and hold the wire in 

- 51 - 

Figure ^41 . Single Wrap for Dropper Attachment 


* * 


4 Y 



>* * 



Figure **2. Figure Eight Wrap for Dropper Attachment 

Figure kl . Figure Eight Wrap for Dropper Attachment to High Tensile Wire 

- 52 - 

place. Thus, they must be attached relatively tightly to the 
wire. At the same time, they must be free to move with the 
wires while maintaining their position on the wires if they are 
to distribute a load of impact among the wires. 

As previously mentioned, the number or spacing of droppers used 
is dependant upon livestock pressure on the fences. The 
greater the livestock pressure on a fence the greater the 
requirement that wire spacings be rigidly maintained, thus the 
more closely spaced droppers should be. 

SUSPENSION. On fences where the wires are relatively close to 

the ground (eight or more wires) it is not recommended that 

droppers touch the ground. This allows droppers to move with 
the wire on impact. 

On fences where the bottom wire is 30 cm or more off the 
ground and where there is small livestock pressure on the 
bottom wires, it is recommended that a dropper (or a post) be 
in contact with the ground every 6 to 9 m . Thus, in an 18 m 
span, with droppers every 3 m, every second or every third 
dropper would be resting on the ground. These droppers drag 
with pressure of small livestock (calves) on the bottom of the 
fence and prevent overturning of the fence. 

METHODS OF ATTACHMENT. Droppers may be stapled, wired, 
clipped or twisted onto line wires. 

1. Droppers that snap on or use clips are easy to install 
without prior instruction. 

2. Spiral twisted wires are placed so the legs of the spiral 
straddle the top wire. Very slight downward pressure and 
guidance by the technician results in the dropper twisting 
itself onto the fence. Remember, these droppers disfigure with 
livestock pressure. 

3. Wooden droppers of sufficient size can be stapled to the 
wires . 

4. Knots for use when droppers are attached 
depicted in Figures 41, 42 and 43. 


i th wi re , are 

Gates are a requirement of all fences. All gates should be: 

- 53 - 

1. located to enhance, not hinder, farm management; 

2 . at least as high as the fence; 

3. wide enough to permit passage of the widest machinery; 

4. level enough, and hinged, to permit free swinging; 

5. as long lived as the fence. 

The wider the gate, the greater its tendency to pull over the 
post on which it is hung. Because of this, gates should be 
installed on end or brace posts to which line wires have been 
tied off. Posts should be at least 244 cm x 152 mm driven 
122 cm into the ground. Gates should be situated several feet 
from corners or perpendicular fences to facilitate machinery 
movement. It may be necessary to offset gates in boundary 
fences along busy roadways. In such cases, panels of boards 
are better than short sections of wire fence. 

The installation of gate hinge pins parallel to fence line 
wires does not allow the gate to swing back against the fence. 
Installing the pins 45 off parallel, on the side of the 
post from which you wish the gate to swing, will allow the 
gate to swing fully back against the fence (Fig. 44) 


V-- ; - : "VOsS 

/ -- 1 

. _ _ 

Figure kk. Hanging Gate at k5 Allows 
it to Swing Fully Back Against Fence. 

A hinged wire gate (Fig. 45) designed by S. Clark Martin at the 
University of Arizona is constructed as follows: 

1. Tightly fasten the end pieces to the diagonal so the frame 
is relatively rigid; 

2. Hang the frame on the hinges or pivot; 

3. Fasten the first wire from the centre of the latch end to 
the centre of the hinge end. 

- 54 - 

4. Tighten the first wire to hold the latch end at the desired 

5. Attach remaining wires, pull them tight enough to hold the 
latch end vertical; 

6. Attach vertical supports as needed; 

7. Tighten the frame so it is rigid; 

8. Materials required: 

a. The diagonal and end pieces can be steel pipe, wooden 
rails or a combination of the two; 

b. The hinge can be two bolted pivots on the gatepost or 
one on the post and a buried pipe in the ground; 

c. Joints between the diagonal and end pieces can be 
welded on tabs, flattened pipe, or screwed on angle 
iron braces for wooden components. They must, 
however, be tight. 




i i 
i l 



Figure *»5- Hinged Wire iate 


Anyone building a wire fence is subject to cuts and scratches 
inflicted by the wire. These can be magnified through care- 
lessness when working with high tension fences. Safety 
precautions should always be followed: 

- 5 5 - 

1. Wear tough clothing that will not tear easily and that 
will not readily catch on wire ends or barbs. 

2. Wear heavy duty, gauntlet type, leather gloves which fit 
snugly . 

3. Wear long pants and work boots with heavy soles to protect 
feet and legs . 

4. Have the right tools for the job, keep tools in good work- 
ing order and follow instructions for tool use. 

5. Wear eye protection when cutting or tensioning wire and 
when driving nails or staples. 

6. Use proper shields on power equipment. 

7. Use a nail apron or tool bag to carry nails, staples and 
tools . 

8. Wear a hard hat and ear protection when operating a post 
pounde r . 

9. Use driving caps on posts to prevent splintering. 

10. Keep children and livestock away from fencing operations. 

11. When working with treated posts or lumber, wear protective 
clothing. Some persons are allergic to chemicals. 

12. Never use unsafe shortcuts. 

13. Keep the work area free from debris; pick up all pieces of 
wire, nails, staples etc. to protect equipment, livestock and 
people . 


The author gratefully acknowledges the assistance of Dr. J. W. 
Zahradnik, Bio Resource Engineering Department, University of 
British Columbia, who developed the basic principles by con- 
ducting a research contract "Study on Cost Reduction of Rangeland 
Fence Construction in British Columbia" funded by Research Branch, 
Agriculture Canada. 

- 56 - 


As with any new technology, sources of materials may be 
initially hard to locate. Because of this, the following 
known suppliers and suggestions are referenced. Mention of 
a product or supplier does not constitute a recommendation by 
Agriculture Canada nor by the author. 

Wire suppliers: 

1. Check your phone book for fencing companies and steel 
companies . 

2. Koppers International Canada Ltd., 8335 Meadow, Burnaby ,B.C 

3. Chilco Industries Ltd., P.O. Box 252, Maple Ridge, B.C. 
V2X 7G1 

4. Sulicher Canada Limited, P. 0. Box 183 Maple Ridge, B.C. 
V2X 7G1. 

5. Davis Wire Industires Limited, 960 Derwent Way, New 
Westminster, B.C. 

6. Tree Island Steel, P. 0. Box 50, New Westminster, B.C. 
V2L 4Y1. 

Hardware suppliers: 

1. Check your phone book for fencing companies. 

2. Koppers International Canada Ltd., 8335 Meadow, Burnaby, B.C 

3. Chilco Industries Ltd., P. 0. Box 252, Maple Ridge, B.C. 
V2X 7G1 

4. Sulicher Canada Limited, P. 0. Box 183 Maple Ridge, B.C. 
V2X 7G1. 

5. Industrial supply firms can supply swagers and compression 
sleeves, but may have to order them. 

Sheet me tal dropper s : 

1. Merrit Machine Works Ltd., 2175 Coldwater, Merritt, B.C. 

2. Spruceview Metalform Ltd., Innisfail, Alberta. 


Metric units 




Results in: 


millimetre (mm) 
centimetre (cm) 
metre (m) 
kilometre (km) 

X 0.04 

X 0.39 

X 3.28 

X 0.62 



square centimetre (cm 2 ) 
square metre (m 2 ) 
square kilometre (km 2 ) 
hectare (ha) 

X 0.15 

X 1.2 

X 0.39 

X 2.5 

square inch 
square yards 
square mile 


cubic centimetre (cm^) 
cubic metre (m^) 
cubic metre (m3) 

X 0.06 
X 35.31 
X 1.31 

cubic inch 
cubic feet 
cubic yards 


litre (L) 
hectolitre (hL) 
hectolitre (hL) 

X 0.035 
X 22 
X 2.5 

cubic foot 




gram (g) 
kilogram (kg) 
tonne (t) 

X 0.04 
X 2.2 

X 1.1 

oz avdp 
lb avdp 
short tons 


litres per hectare (L/ha) 
litres per hectare (L/ha) 
litres per hectare (L/ha) 
millilitres per hectare (mL/ha) 
tonnes per hectare (t/ha) 
kilograms per hectare (kg/ ha) 
grams per hectare (g/ha) 
plants per hectare (plants/ ha) 

X 0.089 
X 0.357 
X 0.71 
X 0.014 
X 0.45 
X 0.89 
X 0.014 
X 0.405 

gallons per acre 
quarts per acre 
pints per acre 
fl. oz per acre 
tons per acre 
lb per acre 
02 avdp per acre 
plants per acre 

C 83-22 

Quinton, D. A. 

High tension high tensile 



3 ^073 OOOIMZM? 3